Insulator



Aug. 12, 1930. K. A. HAWLEY 1,772,513

INSULATOR Filed Oct. 25, 1924 2 Sheets-Sheet 1 dad.

Iii/x7666 Aug. 12, 1930. K. A. HAWLEY INSULATOR Filed Oct. 25, 1924 2 Sheets-Sheet 2 Wf/ness W 6 2% W I 9/ flfl onmq Patented Aug. 12, 1930 UNITED STATES PATENT OFFICE ASSIGNOR TO LOCKE INSULATOR COR- A CORPORATION OF MARYLAND IN SULAT OR Application filed October 25, 1924. Serial No. 745,881.

The invention relates to suspension insulators, particularly to attachments or accessories for use therewith.

The object of the invention, generally stated, is the provision of means associated or connected with a string of suspension insulators of the Hewlett or any other type dis posed beneath the lowermost insulator of the string for the purpose of insuring wetting of the underside of the lowermost insulator during rain storms, to an extent equaling the wetting of the undersides of all the other insulators in the string, it being understood that all the insulators other than the lowermost one are splashed on their undersides by the impingement of rain drops against the insulator next below.

It is well known that a large percent of insulator flash-overs occur during rains when all surfaces of the insulators are wet with the exception of the bottom surface of the lowermost one. It follows, of course, that the resistance of all of these insulator surfaces, except the bottom surface of the lowermost one, is greatly reduced and as the voltage drop across surfaces which are to be consid ered as conductors is directly proportional "to their respective resistances, it follows that a very large percentage of the voltage be- .tween the transmission wire and the ground becomes concentrated across this bottom surface of the lowermost unit. In actual practire-it has been discovered by laboratory and other tests that with long strings of insulators this voltage may beas great as forty .percent of the voltage to the ground.

It is with the above facts in view that I have designed the present invention which has for a more specific object the provision of-an accessory or attachment located at or below the lowermost unit of a string of insulators and so constructed and arranged that when rain drops fall thereupon they will be caused to splash upon and thoroughly wet the underside of the lowermost unit in the string so that the bottom surface of this lowermost unit will be wetted as thoroughly as all the other units in the string.

A still more specific object of the invention is the provision of an attachment or device in the nature of a deflecting pan located beneath the lowermost unit of a string of insulators and having a top surface equivalent to the top surface of an ordinary unit so asto have substantially the same effect in deflecting splashed rain upwardly, the pan being, however, capable of being made of light construction inasmuch as it has practically no weight but its own to sustain.

A further object of the invention is the provision of a deflector pan of this character which may be used as the support for a plurality of clips which operate in conjunction with similar clips mounted. or supported at the top of a string of insulators to serve as arcing horns.

Yet another object is the provision of a splash or deflector pan for the purpose specilied which may be utilized as a support for a shielding ating in conjunction with a more or less similar ring located at the top of the string and mounted in a well-known manner for the purpose of insuring a more or less constant or stable field about the insulator by distributing the voltage whereby to avoid electrical stresses which might result in injury to the insulator units.

To the attainment of the foregoing and other objects and advantages, the invention consists in the construction and arrangement of parts to be hereinafter fully described and claimed, and illustrated in the accompanying drawings, it being, however, understood that various changes and modifications in the details may be made to increase the field of usefulness, provided such variations constitute no departure from the spirit of the invention or the scope of the claims hereunto appended.

In the drawings wherein like reference characters designate corresponding parts throughout the several views:

Figure .1 is a side elevation of a string of insulators equipped with my device and showing the use of grading rings in association therewith.

Figure 2 is a top plan view.

Figure 3 is a detail cross section through the splash pan.

device such as a grading ring oper- Figure at is a side elevation similar to Figure 1 showing the same construction ot insulators or insulator units strung together in series by means of the suspension elements 2, as is a common practice. The insulators disclosed are of the Hewlett type though it should be understood that this particular variety is shown only for purposes of illustration as it is quite evident that other types may be used in connection with my invention. The top surfaces of the insulator units are convex and curved. and it will be quite obvious that during a rain the drops will strike against the top surface of the in sulator units and splash upwardly, thereby wetting the under-surfaces of the units above. However, in the ordinary construction there 1 is no provision whatsoever for wetting the under-surface of the lowermost unit.

In carrying out the present invention I provide a deflector or splash producing element 3 located beneath the lowermost unit in the string and suspended therefrom as clearly indicated. Yhil it is quite true that this deflector element might be constructed in various ways, I have, for the purposes of illustration, shown it as being of trustro-conical form, though the pitch does not necess rily e01 erm to that of the top surfaces of the insulator units. In actual practice it is preferable that the diameter of this deflector member be substantially that of the insulator unit though there is no limitation in this respect as variations may be made it found advisable. It is likewise true that the member 3 mightbe formed or" the same material as the insulator units themselves though I have found it convenient to construct it of metal which might be cast, stamped or otherwise formed to have the desired shape.

As illustrated in the drawings, the member 3, which may conveniently be called a pan, is of irusto-conical or tapered shape and formed or metal. This pan member is located between the lowermost unit and the strain clamp customarily provided, indicated at 4c, the actual suspension means being, for example, the type shown and including a two-part shell having openings i accommodating the arms of the suspension link 2, the headed ends of which are located within the shell. The shell sections are secured together by a transverse bolt i equipped with a nut i. The clamp 4, which is of ordinary type, is shown as suspended from a pin l traversing a clevis a having an upstanding stem passing through the center of the pan 3 shell, the end being upset or headed at 4 In Figures 1 to 3, inclusive, I have shown a grading ring 5 at the top of the string of insulator units, which ring is carried by a plurality 01" arms 6 radiating from a sup port 7 suitably connected with the uppermost insulator unit and provided with a suspension element 8 of convenient type, such as the eye illustrated. In this form, the pan 3 is shown as equipped with plurality of radial arms 9 which carry a similar grading ring 10 spaced. considerably from the lowermost unit of the stron and corresponding to the ring 5, these rings acting in a well known manner to shield the insulators. The inner ends of the arms 9 are disclosed as extended upwardly 11 and apertured for connection with the transverse bolt i so as to avoid the interposition of an auxiliary attaching device.

In the use of device constructed and arranged as shown, it is evident that whenever rain strikes against the pan 3 it will splash and effect a thorough wetting of the undersurface of the lowermost insulator unit in the string equal to the wetting of the lowermost surfaces of all the other units by the impingement and consequent splashing of rain drops falling upon the insulators next be low so that the undersides of all the units will present the same resistance to the pars sage of: current, thereby effecting grading of the electrostatic held preventing unequal electrical strains and obviously reducing likelihood of flash-overs.

In Figures 4-, 5 and G I have disclosed the same type of pan 8 but instead of providing the grading rings 5 as above described, I make use of arcing horns 13 carried by a supporting element 14: at the top of the string equipped with a suspension eye 15 or the like, and further make use of clips 16 secured upon the pan 3 and projecting in an upward and outward direction so as to define arcing horns cooperating with the horns 13 for taking care or any flash-over and preventing injury to the insulators in the string. The number of horns or clips provided may, of course, vary under different circumstances or conditions and the number illustrated may be increased or decreased in accordance with what is found to be most advantageous. As a matter of electrical design. the edge of the pan 3 is rolled, turned or deflected inward-.

ly. as shown at 17, for the purpose of avoiding or preventing corona points.

A splash insuring device constructed in accordance with this invention will be found to be of material advantage inasmuch as it will prevent any difference between the conand the bottom of the dition of the undersurface of the lowermost unit in a string of insulators, and the corresponding surfaces of other units and thereby preventing any difference in the conductivity of the surfaces and making them all have substantially the same resistance, this uniformity acting to prevent likelihood of flashovers and possibility of damage to the bottom insulator unit because of the too high in voltage being impressed upon it.

Having now described my invention, what I claim is:

1. In combination with a string of insulator units, a conductor clamp and means suspending the clamp from the string, a splash producing pan located beneath the lowermost unit of substantially frusto-conical form whereby rain water impinging thereupon will be splashed onto the undersurface of the lowermost unit, said pan being open at its top to accommodate said sus ension means and having means at its top f hr connection with said suspension means.

2. In combination with a string of suspension insulators, a conductor clamp and a suspension link interposed between the lowermost insulator and the clamp, a splash producing member located beneath the lowermost insulator unit and having an opening 29:0 for the accommodation of said suspension link, and spaced attaching members at the top of said splash producing member adapted to be connected with said suspension link.

In testimony whereof I aflix my signature.

as KENT ALLEN HAWLEY. 

